Once you understand that you have rights to protect it is time to add Boundaries to the tool box.  You can review the page that I have on boundaries.  https://ptsd-acceptingcopingthriving.com/coping/boundaries/

These are the books on Boundaries that my counselors suggested:
Boundaries by Dr. Henry Cloud & Dr. John Townsend
http://store.cloudtownsend.com/boundaries-softcover-book.html
http://www.amazon.com/Boundaries-When-Take-Control-Your/dp/0310247454
This book is based on the Bible with many scripture references.  I prefer this approach. It also started with the very basics such as the first boundary being our skin.

Boundaries and Relationships: Knowing, Protecting and Enjoying the Self by Charles Whitfield
http://www.amazon.com/Boundaries-Relationships-Knowing-Protecting-Enjoying/dp/155874259X/ 
My counselor recommended this book and I found it gave me a broader understanding of boundaries.

Yup, I read two books specifically on boundaries.  Plus, many other books also refer to the importance of boundaries.  I like what a counselor told my sister, “You don’t need to set boundaries with a healthy person because they have them too and expect you to have them.”  Boundaries are set for those individuals that don’t respect the rights I set for myself.  I appreciate one of my counselors examples.  He knew I lived in the country for several years.  There is an understanding in the country if you open a gate you shut it.  All of the ranches had fences and gates.  Fences are designed to keep unfriendlies out and important things in.  Gates are designed to let in those that are safe.  In this metaphor, he went on to explain that the outer most fence is for all those that we meet briefly day to day probably not even knowing their names.  They are allowed on the outside of my boundaries farthest from my home/heart.  Then there are those that I trust to have some interaction and come in the first gate.  Then there is a second fence around my house and more private living space. These are coworkers, people in my neighborhood, and acquaintances.Those that I allow into my house are my friends.  Then come in the living room, share my kitchen but I don’t let them into my bedroom.  There only my closest most intimate friends and family are allowed.  By visualizing these multiple layers of boundaries, gates, and allowing others closer to me, I am better able to understand how much I share with others.  I also keep in mind that someone betrays my trust I can escort them back out of a gate.  I was chatting with a friend of mine talking over the frustration of someone violating a boundary and then being astonished that the violation ended their friendship.  Do people make mistakes? Sure.  But it requires a certain amount of regaining privileges, time to establish they are safe enough to let back inside my boundaries.

What does a boundary look like? A simple example, I don’t buy things door-to-door.  I politely tell them, no thank you.  If they get pushy, then they are violating my boundary and I shut the door.  I had boundaries, I simply didn’t recognize what they were.  I also was not in the habit of protecting them.  Amazing things happened when I started protecting my own boundaries and knowing that I established them.  For me, I am constantly reviewing and adjusting boundaries.  I now recognize that a healthy boundary helps me to protect myself without putting myself in a straight jacket.  By the way, one of the consequences of boundaries is those that violate your space will call you mean for putting up boundaries and protecting them.  I learned to acknowledge, yes I used to let you violate my space but I am not that way any more, things in my life are changing.  I noticed that my friends cheered me on and supported my efforts.  Abusers fought me and called me names or tried to bully me back into being a door mat.  My counselor helped me to firmly and steadfastly protect my boundaries.  I am a happier person knowing that those that tend to attack are securely placed behind strong high boundaries.  Those that are safe to be with are allowed a closer relationship with me.  It is working and continuing working after I stopped counseling.  I would say Boundaries is one of the most valuable tools in my toolbox.